A need exists for improved linear, tunnel-type, box-type, spiral, and other industrial combustion (e.g., gas) ovens and oven systems for cooking food items, or for heating and/or drying other items or materials, as the items or materials are continuously, semi-continuously, or intermittently delivered through the oven. A need also exists for a means of significantly reducing temperature differences and substantially eliminating the presence of cold and/or hot pockets within these combustion-type systems.